A filling pipe arrangement of this kind, known in the prior art as a “filling head” or the like, is known for example from EP 2 719 567 A1.
Such filling pipe arrangements make it possible to introduce the output end section of the delivery device into the passage at their end away from the tank, i.e., the lengthwise end closer to the inserting mouth, in order to pour in the fluid being delivered into the automotive fluid tank connected to the filling pipe arrangement with the fewest possible losses. Precisely in the case of the operating fluid which is preferably considered, namely, aqueous urea solution for selective catalytic exhaust gas cleaning, the avoidance of losses serves not only for the most effective use of the operating fluid, but also the avoidance of nuisance odor outside the filling pipe arrangement and outside the automotive fluid tank for users of the respective vehicle or attending and maintenance personnel working on the vehicle.
After introducing the output end section into the inserting end section of the filling pipe arrangement, the delivery device can discharge the fluid being delivered directly into the passage of the filling pipe arrangement. For this, one region of the passage is fashioned as a conducting section, which takes the operating fluid discharged from the output end section through the filling pipe arrangement until it finally emerges at the discharge opening.
At the discharge opening, either the volume of a tank connected to the filling pipe arrangement may be present directly, or there may be a further pipeline section, for example, one in the form of a pipe or hose attached to the filling pipe arrangement, which takes the fluid emerging from the discharge opening further onward to the tank.
Precisely in the application for aqueous urea solution as the preferred operating fluid, the conducting of this operating fluid through the filling pipe arrangement occurs with large volume flow of up to 40 liters or more per minute, which may result in intense secondary reactions, such as sloshing of the fluid in the tank, overflow, and so-called “spit-back”. These secondary effects in turn may lead to undesirable emergence of fluid already introduced into the filling pipe arrangement or even into the automotive fluid tank.
The filling pipe arrangement of this kind has a magnetic arrangement whose magnetic field reaches into the passage so that with the aid of the magnetic arrangement it is possible to detect the proper presence of the output end section of the delivery device, from which further consequences for the subsequent filling process may be inferred.
For example, the output end section of the delivery device may be outfitted with a valve responding to the magnetic field of the magnetic arrangement, which only allows a passage of operating fluid in the delivery direction to the discharge opening when the output end section and the magnetic arrangement assume a predetermined relative position, which is advantageously the case only when the output end section of the delivery device is properly introduced into the inserting end section.
The valve may be passive in design, i.e., upon reaching the predetermined relative position between output end section and magnetic arrangement the valve is moved by the magnetic field of the magnetic arrangement from a closed position to an opening position and remains there for as long as the predetermined relative position between output end section and magnetic arrangement continues. It may thus be prevented that a delivery of operating fluid continues when the output end sections is pulled out from the inserting mouth of the filling pipe arrangement even though, based on the change in position of the output end section, a correct filling of the operating fluid into the filling pipe arrangement is no longer assured.
The aforementioned large delivery volumes of modern delivery devices and the concomitant secondary effects furthermore make it essential to carefully watch the filling process in order to prevent an overflow of the automotive fluid tank being filled or quite generally an escaping of operating fluid against the delivery direction from the inserting mouth. Here as well interactions between the fluid filled with high volume flow rates into the tank and the gas displaced in this way from the tank and the filling pipe arrangement play a major role.
Therefore, the problem which the present invention proposes to solve is to modify the filling pipe arrangement of this kind so that an escaping of operating fluid against the delivery direction from the inserting mouth of the filling pipe arrangement is prevented as reliably as possible with the most simple and economical means possible during a filling process.